|
|  |
|
|
|
| |
| Jul 02, 2007 9:18 pm |
|
Problem with pavement |
Ken Hilving
| |
On another discussion, the issue of roads got raised.
I think it is worth taking a logical look at roads, and their expansion as the primary mode of transportation. Since roads are common place, we tend to ignore their impact.
Rainwater has to be considered when building roads. A road has two impacts. First it removes the water absorption capability of the area it sits on. Next, it generates an immediate requirement to handle runoff water. This second impact is not a trivial issue, as the folks here in north and central Texas can attest to as we move from drought to record rainfalls.
Using the standard lane width for US Interstate highways (12 feet) and assuming paved shoulders on both sides of each direction of the highway (40 feet total), we can look at just how much runoff is generated by a 30 mile urban artery during an inch of rainfall.
- 4 lane highway 6,732,000 gallons
- 6 lane highway 9,108,000 gallons
- 8 lane highway 11,484,000 gallons
We officially had 27 inches of rain in June, with significant flooding, erosion of stream and river banks, reservoirs exceeding capacity, and major property damage. There were also several deaths, although I tend to consider these self inflicted or suicide by stupidity.
This runoff did not get absorbed in order to recharge area aquifers and other groundwater systems.
Pavement retains heat, increasing the local temperature during the summer of urban and suburban areas. In the 10 miles between where some good friends live and where I live, there is a 10 degree temperature difference. They are in a suburban neighborhood, while I live in what still passes for rural. Likewise, traffic in their area generates a constant background noise level. When friends and family visit, they invariably comment on the quiet and how nice that is.
Last year in the US, there were 43,000 traffic deaths. A good portion of these occurred when two or more vehicles tried to occupy the same space at the same time. With the exception of our limited access highways, roads, railroads, and pedestrian crossings use a common plane where their paths cross.
The direct cost of highway building comes from federal and state highway department monies. Fuel taxes do not cover these costs, so other tax sources and tolls are used.
Indirect costs include the removal of land from other uses, disruption of local business, and through the disruption of pedestrian traffic patterns communities become "islands". Highways in rural and natural environments disrupt migratory patterns and create "islands" of habitat detrimental to plants and animals. Road kill is another hazard for both animals and drivers. Businesses and homes lost to road construction are also lost to that community's tax base and job base.
Perhaps the biggest drawback with road traffic as we have done historically is its inability to handle increased traffic. Gridlock is becoming common in many urban areas, and highways are running out of space for expansion. Complaints of being stressed out by traffic are increasing.
___
Innovative new transportation systems should, at a minimum, address the problems we have with pavement by doing no worse on any and better on some.
Private Reply to Ken Hilving (new win) |
|
| |
|
